1. Field of the Invention
The present invention relates to a method and apparatus for correlating volume or line measurements to volume or point estimates of the measurement. One example of such a system is a multi-target tracking system, which correlates volume measurements of an object from a known position, wherein the object and the known position are moving relatively to each other, to a volume measurement estimate of the position or the like of the object made from an extrapolation of a track of the object, wherein the track is generated from previous volume measurements of the object.
2. Description of Related Art
Multiple-target tracking (MTT) systems are necessary whenever a sensor and a plurality of objects or the like are moving relative to each other. Common physical examples of multiple-target tracking include 1) tracking of airborne, space traveling, or water borne objects such as aircraft, satellites and other orbiting objects, or submarine and other naval craft; 2) tracking of objects moving in a fluid or pneumatic line, such as cells or other objects in a vein or soot particles and the like in a smokestack; 3) tracking of objects or particles in a simulation of a physical system; and 4) tracking of virtual objects in a virtual reality.
In any MTT environment, a limiting factor in the accuracy and usefulness of the system is the ability to correlate n sets of present measurements of location data (or the like) of n objects with n tracks generated from previous measurements. A brute force method of comparing every one of n tracks to everyone of n measurements requires n.sup.2 *t.sub.(n) time, where t.sub.(n) is the average time per comparison. Clearly, for all but the most trivial problems, pure brute force comparison to determine which measurement corresponds to which track cannot be done in real time.
Accordingly, it is well known that computational efficiencies can be obtained by first identifying those tracks which are most likely to correlate to a particular measurement, and comparing by brute force only those identified tracks. If sufficient computational efficiencies are obtained, it is possible to correlate n measurements with n tracks in real-time.
MTT is one example of a general system which generates a measurement defining a volume or a line, and an estimate of the measurement which is defined as a volume or a point, wherein a limiting factor of the general system is the ability to correctly and efficiently correlate a plurality of volume or line measurements to a plurality of volume or point measurement estimates.